[Exim] SMTP Timeouts sending mail

Hi All,

We've started having problems with clients sending mail via exim.
All our users mail clients e.g. outlook, pegasus, outlook express etc
are throwing up timeout errors when sending mail. Telnetting to
the mail server's SMTP port take upwards of 70 seconds to display
the banner.

I have checked the 4 options in the FAQ on this problem and the status is
as follows

1. (rfc141_query_hosts and rfc1413_query_timeout)
Neither appear in the main configuration - does this mean they are disabled?
2.(rbl_domains and rbl_hosts)
Disabled
3.(host_lookup)
Disabled
4.(sender_verify_hosts_callback and sender_verify_callback_domains)
Neither in main configuration.

The system is a Linux box running 2.2.17-21
Exim version 3.22

Any help gratefully received

John

John Wilson
Computer Officer
EEE Dept
Strathclyde University
email: j.wilson@???
tel: 0141 548 2512
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